Breast Cancer Prevention
Breast Cancer Prevention
Clinical Services Department MC-21
What is Breast Cancer?
- Cancer is a disease in which cells in the body grow out of control.
- Breast cancer is a disease in which malignant (cancer) cells form in the tissues of the breast.
- A breast is made up of three main parts: lobules, ducts, and connective tissue. The lobules are the glands that produce milk. The ducts are tubes that carry milk to the nipple. The connective tissue (which consists of fibrous and fatty tissue) surrounds and holds everything together. Most breast cancers begin in the ducts or lobules.
- The kind of breast cancer depends on which cells in the breast turn into cancer.
- The most common types are invasive ductal carcinoma and invasive lobular carcinoma, which can spread or metastasize to other parts of the body. Ductal carcinoma in situ, is also a type of breast cancer that have not spread to other tissues of the breast.
Breast Cancer Statistics:
- Breast cancer is the second most common type of cancer in American women.
- It is second to lung cancer as a cause of cancer death in American women.
- Breast cancer also occurs in men, but the number of new cases is small.
- In Puerto Rico (P.R.), the incidence of breast cancer in female patients is 29.7% and it is the type of cancer with the highest incidence in the island.
- Mortality rates for breast cancer in P.R. account for 18.9 % of the female population.
Breast Cancer Risk Factors:
- Older age
- Personal history of breast cancer or benign (non-cancer) breast disease
- Inherited risk of breast cancer
- Dense breast – Having breast tissue that is dense on a mammogram
- Exposure of breast tissue to estrogen made in the body – Being exposed to estrogen over a long time may increase the risk of breast cancer. Estrogen levels are highest during the years a woman is menstruating. Other factors the increase estrogen levels:
o Early menstruation
o Starting menopause at a later age
o Older age at first birth or never having given birth
- Taking hormone therapy for symptoms of menopause, such as estrogen and progesterone, which may be given to replace the estrogen no longer made by the ovaries in postmenopausal women or women who have had their ovaries removed.
- Radiation therapy to the breast or chest – increased risk can be seen 10 years after treatment.
o The risk of breast cancer depends on the dose of radiation and the age at which it is given.
o The risk is highest if radiation treatment was used during puberty, when breasts are forming.
o Radiation therapy to treat cancer in one breast does not appear to increase the risk of cancer in the other breast.
- Drinking alcohol
Breast Cancer Prevention Strategies:
- Decreasing the length of time a woman’s breast tissue is exposed to estrogen may help prevent breast cancer:
o Early pregnancy and breast feeding (if possible), result in lower estrogen levels.
- Keep a healthy weight and exercise regularly – Women who exercise four or more hours a week have a lower risk of breast cancer. Most healthy adults should aim for at least 150 minutes a week of moderate aerobic activity or 75 minutes of vigorous aerobic activity weekly, plus strength training at least twice a week.
- Don’t drink alcohol or limit alcohol intake to less than one drink a day.
- Don’t smoke.
- Limit dose and duration of hormone therapy – more than three to five years increases the risk of breast cancer.
- Avoid exposure to radiation and environmental pollution.
- Women who have a high risk of breast cancer may choose to have a risk-reducing mastectomy (the removal of both breasts) when there are no signs of cancer.
- Estrogen-only hormone therapy after hysterectomy – In these women, estrogen-only therapy after menopause may decrease the risk of breast cancer, but post-menopausal women might be at risk for stroke and heart and blood vessel disease.
- Taking selective estrogen receptor modulators, such as raloxifen and tamoxifen, which act like estrogen on some tissues in the body, but block the effect of estrogen on other tissues, may lower the risk in pre and postmenopausal women at higher risk.
o With either drug, the reduced risk lasts for several years or longer after treatment is stopped.
o Side effects include blood clots in lungs and legs, and hot flashes. It is important to talk with your doctor about the risks and benefits of starting one of these drugs
- Use of aromatase inhibitors (anastrozole, letrozole) and inactivators (exemestane) lower the risk of recurrence and of new breast cancers in women who have a history of breast cancer.
For Additional Information on Breast Cancer Prevention:
• National Cancer Institute: www.cancer.gov
• Mayo Clinic: www.mayoclinic.org
• Centers for Disease Control and Prevention: www.cdc.gov/cancer
• Medline Plus: www.medlineplus.gov